1. Field of the Invention
The present invention relates to lamp wiring structure and socket coupling structure and relates to, in particular, the wiring structure between a lamp and a connector suitably used for a rear combination lamp, a front combination lamp and the like of a vehicle and the coupling structure of a bulb socket provided with a lamp.
2. Description of the Related Art
Normally, a rear combination lamp of a vehicle comprises a rear combination lamp housing substantially formed entirely by a transparent member and fixed to the rear part of the body of the vehicle, and a lamp unit installed at the rear combination lamp housing and having lamps each of which emitting light toward the rear of the vehicle via the rear combination lamp housing when driving current is applied to the lamp. The lamps of the lamp unit are fixed to the corresponding lamp containers of the rear combination lamp housing, respectively.
Specifically, the rear combination lamp housing of the rear combination lamp is structured mainly by the transparent member such that shapes of end portions thereof are flush with shapes of the rear part of the body of the vehicle in the vicinity of the both end portions of the rear combination lamp housing and such that the lamp containers are formed on the reverse face of the central portion of the rear combination lamp housing. While the rear combination lamp housing contacts with the rear part of body of the vehicle, each of male fasteners is correspondingly inserted into a female fastener provided at the body of the vehicle, thereby fixing the rear combination lamp housing to the body.
Also, the lamp unit of the rear combination lamp typically comprises a bulb socket to which a two-circuit type lamp is installed, a bulb socket to which a single-circuit type lamp is installed, a connector detachably coupled to a connector provided at a harness on the body side of the vehicle, and a wire harness having one end connected to the connector and the other end correspondingly connected to the bulb sockets, respectively. While the connectors are coupled to each other and the two lamps are installed at the corresponding bulb sockets, respectively, the bulb sockets are inserted into and fixed to corresponding lamp containers of the rear combination lamp housing, respectively.
The wire harness of the lamp unit in the rear combination lamp comprises two electric wires for connecting the bulb socket into which the two-circuit type lamp is inserted and the connector of the lamp unit, an electric wire for connecting the bulb socket into which the single-circuit type lamp is inserted and the connector of the lamp unit, the first common electric wire for connecting the bulb sockets to each other and the second common electric wire having one end connected to the first common electric wire in mid course and having the other end connected to the connector. When driving current is outputted from the connector, current is supplied to one of or both of the lamps so as to light the lamp or the lamps.
In the rear combination lamp of this type, however, the lamp unit consists of two bulb sockets, a connector and a wire harness. The number of parts is, therefore, excessively large and it is difficult to realize a cost reduction.
It is also required that the bulb sockets are inserted into the corresponding lamp containers of the rear combination lamp housing, respectively and the lamps are fixed into the corresponding lamp containers, respectively. These operations have to be sequentially conducted, thereby taking much time for installation.
Moreover, in case of a normal bulb socket such as, for example, a bulb socket into which a single-circuit type lamp is inserted, the following operations are required. Namely, a lamp is inserted into a lamp insertion hole formed in the lamp container. Two claws formed at the bulb socket are inserted into grooves provided in the lamp container. The bulb socket is pushed until a flange provided at the bulb socket comes into contact with the reverse face of the lamp container. The bulb socket is then rotated and the two claws formed at the bulb socket are engaged with lock grooves provided in the lamp container, thereby fixing the bulb socket to the lamp container. In this process, both the operation of pushing the bulb socket toward the lamp container and that of rotating the bulb socket have to be conducted, for which, it takes more time for installation.